This article presents a high-resolution chronology of Wairajirca pottery in the Huánuco basin, which has been identified as a frontier region between the Andean highlands and the Amazonian rain forests: its pottery is known for having mixed features from both areas. However, the lack of fine-grained pottery and radiocarbon datasets has handicapped comparative studies’ attempts to track in detail its early development process. Our new high-resolution chronology of Wairajirca pottery is based on stratigraphic excavation data, a detailed ceramic typology, and a Bayesian analysis of the radiocarbon date from the Jancao site. The five-staged ceramic sequence from the late eighteenth to late twelfth century cal BC displays specific features of this development, including radical changes in vessel type over several centuries and connections with other pottery traditions. The earliest phase shows close relation with highlands traditions, whereas the influence of tropical rain forest patterns intensified in later phases alongside the continuation of local pottery traditions. This indicates that frontier dynamics based on fluid interactions across different ecological zones and regional sociopolitical movements played a crucial role in this long-term social process.